export default {
	// 为当前模块开启命名空间
	namespaced:true,
	
	//模块的state数据
	state:() =>({
		cart:JSON.parse(uni.getStorageSync('cart') || '[]' )
	}),
	
	//模块的mutations方法
	mutations:{
		addToCart(state,goods){
			const findResult = state.cart.find((x) =>x.goods_id=== goods.goods_id)
			
			if(!findResult){
				// 如果购物车中没有这个商品,则直接push
				state.cart.push(goods)
			}else{
				// 如果购物车中有这件商品,则只更新数据即可
				findResult.goods_count ++
			}
			this.commit('m_cart/saveToStorage')
		},
		saveToStorage(state){
			uni.setStorageSync('cart',JSON.stringify(state.cart))
		},
		//更新购物车中商品的勾选状态
		updateGoodsState(state,goods){
			const finResult = state.cart.find(x => x.goods_id === goods.goods_id)
			
			if(finResult){
				finResult.goods_state = goods.goods_state
				
				this.commit('m_cart/saveToStorage')
			}
		},
		
		// 更新商品的数量
		updateGoodsCount(state,goods){
			const findResult = state.cart.find(x =>x.goods_id === goods.goods_id)
			
			if(findResult){
				findResult.goods_count = goods.goods_count
				this.commit('m_cart/saveToStorage')
			}
		},
		
		// 根据ID删除对应的商品
		removeGoodsById(state,goods_id){
		state.cart = state.cart.filter(x => x.goods_id !== goods_id)
			
			this.commit('m_cart/saveToStorage')
		},
		updateAllGoodsState(state,newState){
			state.cart.forEach(x => x.goods_state = newState)
			
			this.commit('m_cart/saveToStorage')
		}
	},
	
	//模块的getters属性
	getters:{
		// 统计购物车中商品的总数量
		total(state){
			// let c = 0
			// //循环统计商品的数量 累加到变量c中
			// state.cart.forEach(goods => c += goods.goods_count)
			// return c
			
		return	state.cart.reduce((total,item)=> total += item.goods_count,0)
		},
		//购物车中已经勾选商品的总数量
		checkedCount(state){
			return state.cart.filter(x => x.goods_state).reduce((total,item)=>{
				return total +=item.goods_count
			},0)
		},
		// 已勾选商品的总价格
		checkedGoodsAmount(state){
		return	 state.cart.filter(x => x.goods_state).reduce((total,item) =>total  +=item.goods_count*item.goods_price,0).toFixed(2)
		}
		
	}
	
}

